Moisture-proof switchboard-cord.



W. L. RUNZEL.

MOISTURE PROOF SWITCHBOARD CORD.

APPLICATION FILED MAY 24. 1915.

1,214,830. Patented Feb. 6,1917.

w: New: PETERS CO1.PHOTO-LIYNOHWASHYNGTUN. 11c.

UNITED STATES PATENT OFFICE".

WILLIAM L. RUNZEL, OF CHICAGO, ILLINOIS, ASSIGNOR 'IO RUNZEL-LENZELECTRIC MIEG. 00., OF CHICAGO, ILLINOIS.

MOISTURE-PROOF SWITCHBOARD-CORD.

To all whom it may concern:

Be it known that I, WILLIAM L. RUNZEL, a citizen of the United States,residing at Chicago, "in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Moisture-ProofSwitchboard-Cords, of which the following is a full, clear, concise, andexact description, reference being had to the accompanying drawings,forming a part of this specification. I

My invention relates to flexible switch board cords and has for itsobject the provision of an improved interconnecting cord of thischaracter which is moisture proof.

Under a great many conditions of operation of telephone switchboards itis found that the dampness in the atmosphere causes short circuits orpartial short circuits between the conductors of the switchboard cordsand thus creates considerable 'difliculty such as the impropertransmission of the voice currents between two connected telephoneinstruments. To avoid the diificulties referred to the problem is thuspresented of rendering a flexible switchboard cord moisture proof. Ihave devised a construction and arrangement of the various elementsentering into the manufacture of a flexible switchboard cord by virtueof which this moisture proof quality is obtained. The cord is not onlymoisture proof when first produced, but retains its moisture proofqualities even under the severe conditions imposed upon it due to itsflexible character.

I will describe one form of cord which may be constructed in accordancewith my invention by referring to the accompanying drawing in which.

Figure 1 is a side elevation of a cord partly unwrapped showing thewrappings in the relation which they bear to each other in my improvedstructure, and Fig. 2 is an enlarged sectional view on line a-a of Fig.1.

My improved cord construction as herein disclosed consists in thebuilding up of a flexible moisture proof cord by superposing a pluralityof layers of material each having its peculiar function. i

The core of the cord consists of a plurality of preferablylongitudinally extending copper tinsel conductors 1. About this iswrapped a helical steel conductor 2 in elec- Patented Feb. 6, 1917.

Application filed May 24, 1915. Serial No. 30,057.

trical contact with the copper tinsel, both together forming the innerconductor. About this inner conductor formed of the parts 1 and 2, Iwrap acovering 3 of silk, linen, cotton, wool, or material of thatnature, having therequisite'insulating characteristics, and-thisinsulating covering of the inner conductor maybe in the form of wraps orbraids as is found most serviceable.

' About this insulating shell 3; I "arrange 'a second conductor of thecord which consists of tinsel 4 preferably braided about the insulatingcovering 3. A helical steel conductor 5 then surrounds the tinselconductor 4, being in electrical contact therewith and the two togetherforming the second conductor of the cord. The cord thus consists of twoconductors as shown. In the event of the requirement of three or moreconductors, the construction above described can be re peated and inpractice I have built up cords of more than two conductors following thelines above laid out. Herein however I am describing merely a twoconductor cord as that will be sufficient to illustrate my invention.About the steel cord-5 with its associated tinsel 4 I then arrange awrapping of insulating material 6which may be silk, cotton, wool, orlinen,-or similar material, but which in the particular cord underconsideration consists of silk, which is treated with an impregnatingwax or moisture proofing material of suitable characteristics so as toresist moisture. About this moisture proof wrapping I then provide anouter or external braid or covering which is customary and which mayeither be of silk, cotton, or linen or similar material as the occasionmay demand. The ends of the cord may then be provided with suitableterminals if desired or the conductors may be brought out withoutterminal attachments to fit the requirements of various connectingdevices to which the cord may be attached.

I have found that the particular arrangement of the moisture proofwrapping in the manner shown in the drawing about the second conductorretains its moisture proof characteristics even under the severeconditions imposed by the flexible character of the cord when in use.

From the above description the nature of my invention will be readilyclear to those that modifications may readily be made within: the scopeof the appended claims without departlng from the spirit ofinyinvention.

Having-however thus described" one form Which my invention may take,W-liatl claim as new and desire to secure by Letters Patent is:

1.,A flexible switchboard cord consisting ing. protectingi coveringabout" said wrapping;.thereby v forming; a' pliable and flexiblemultiple conductingcordu 4 c opiea "on thii patent may be obtained tor2. A flexible switchboard cord consisting of a flexible inner conductoradapted to form part of" an electric circuit, a concentric fieX- ibleouter'cond'uctor adapted'to form part of an electric circuit, saidconductors being concentric and helically wound, insulation between saidconductors, a layer of insulating material impregnated with a moistureproof compoundsurrounding said OlltQFCOl'ldllCtOI, and aflexibleinsulating protecting covering about said moisture proof layer,thereby forming a pliable: andi fieX-iblemultiple con ducting' co rd: 7

In Witness whereof, I hereunto subscribe my name this-5th day of May, A.D, 1915..

. WILLIAML. RUNZ'EL.

Witnesses:

- HnzEnA-I. J'oNEs, MAX W. ZABEL.

five cents each,. by.- addressing the Commissioner cilia-tents,Washington, D. 0.

